A temperature-regulated system for printing presses is disclosed in DE 694 02 737 T2. A compression device selectively makes available a temperature-regulating medium for cooling, as well as for heating purposes, which medium is usable for regulating the temperature of inking system rollers of several printing attachments. This takes place by the selective provision of a heat exchanger with the compressed temperature-regulating medium, which medium is subsequently cooled in a condenser and is finally expanded and, in the other case by the use of a bypass with a non-expanded, and therefore hot, temperature-regulating medium. Either cooling or heating of a secondary circuit of a temperature-regulating medium, passing through the rollers, takes place in the heat exchanger. Regulation of the temperature of the medium in the secondary circuit takes place by metering this temperature-regulating medium by the use of a temperature sensor and with a control valve in every individual roller.
A system for temperature regulation is known from DE 296 08 045 U1. A first cooling device, with a first cooling process and with a first fluid circuit, is provided for cooling a dampening medium and is thermally connected, on the one hand, via a heat exchanger with the dampening medium supply circuit for the dampening medium and, on the other hand, thermally, via a second heat exchanger, with a second fluid circuit, which second fluid circuit, in turn, is thermally coupled with a second cooling process configured as a cooling tower.
DE 44 26 083 A1 discloses a temperature-regulating arrangement. A temperature-regulating fluid, for regulating the temperature of a roller, can be conducted, in its circulation, to be selectively in thermal contact, via a heat exchanger, with a cooled fluid circuit, or via a heating heat exchanger.
Methods are known from WO 03/045694 A1 and from WO 03/045695 A1 wherein, by regulating the temperature of a rotating component of a printing attachment, which works together with printing ink, the tackiness of the printing ink on the rotating component can be maintained substantially constant within a temperature range between 22° C. and 50° C. The tackiness of the printing ink is a function of the temperature on the shell face of the rotating component and the production speed of the rotating component. Application of these methods consist, in particular, in a waterless-printing attachment, and preferably in a printing attachment for newspaper printing.
EP 0 652 104 A1 discloses a printing attachment for waterless offset printing. A regulating arrangement is provided with several regulating devices which, for preventing the buildup of printing ink on a transfer cylinder of the printing attachment, regulate, based on a desired value, a respective control valve for regulating the amount of a coolant, such as, for example, water, that is supplied to the respective cylinders. The regulation is accomplished as a function of the deviation from a temperature determined by a respective thermal sensor at the transfer cylinder, or at a forme cylinder of the printing press which is assigned to the transfer cylinder, or at an ink distribution cylinder of an inking system which is assigned to the forme cylinder. Maintaining the temperature of a printing forme, which is arranged on the forme cylinder, constant during the printing process by the use of the regulated amount of coolant is made possible, for example, within a temperature range between 28° C. and 30° C. The temperature of the transfer cylinder is to be maintained at approximately 34° C. to 35° C. and the temperature of the inking system is to be maintained between 25° C. and 27° C. Along with the supply of an amount of coolant, there is also provided an option for pre-warming the printing system. The result is that plucking of the printing ink at the start of printing, together with the collection of paper particles in the inking system, can be prevented. A temperature curve of the coolant, for pre-warming, can be regulated in accordance with a temperature-time curve entered, for example, into a memory unit which is housed in the regulating device.
A temperature-regulating device in a printing attachment is known from DE 197 36 339 A1/B4. The rheological properties, such as, for example, tackiness, among others, of printing inks and other fluids are affected by the temperature regulation. The associated printing press, with a forme cylinder, has a short inking system with an ink duct, a screen roller and an ink application roller. At least one of the inking group rollers, or the forme cylinder, can be temperature-regulated by the temperature-regulating device. Temperature regulation takes place by cooling or by warming from either the direction of the shell face of the inking system rollers or of the forme cylinder, or in the interior of the inking system rollers or the forme cylinder. In addition, the temperature of the ink duct can also be regulated, and in particular also the temperature of the doctor blade for removing excess printing ink from the screen roller. The amount of printing ink which is transferred to the forme cylinder can be regulated by the use of a control loop. An optical density, which is measured on the material to be imprinted, is used as the signal value, by the use of which the regulating device, which is assigned to the temperature-regulating device, regulates their temperatures.
DE-OS 19 53 590 discloses a printing attachment with an inking system and a dampening system, the temperature of which can be regulated by the use of a temperature-regulating device. A desired value of the temperature can be determined as a function of influencing variables, such as, for example, the printing speed, prior to the start of the printing process, or can be set by the use of tables. An advantageous upper limit of the temperature of the printing ink is stated to be the room temperature.
It is known from DE 39 04 854 C1 that the speed of rotation of the cylinders of the printing attachment, of the inking system and of the dampening system, have an effect on the inking system temperature.
In DE 44 31 188 A1 a printing forme of a printing attachment for waterless offset printing is cooled to approximately 28 to 30° C.